Controlling liquid media including solid matter suspended therein



Oct.

I H. KLOPPEL CONTROLLING LIQUID MEDIA INCLUDING SOLID MATTER SUSPENDED THEREIN Filed Dec. 11, 1959 United States Patent 3,106,933 CONTROLLING LIQUE IVEDIA INQLUDZNG SOLE MATTER SUSIPENDED THEREEN Heinz Kliippel, Ruckershausen uher Bad Schwalhach,

Germany, assigior to Passavant-Werire, Micheihaeherhutte, near Mieheihach, Germany Filed Dec. 11, 1959, Ser. No. 3,705 Claims priority, application Germany Dec. 13, 1958 2 Claims. (Ci 137--89) This invention has reference to systems for controlling the flow of liquids including comminuted solid matter suspended therein in disperse form.

Systems of that kind may be comprised, for instance, in sewage processing plants, or industrial sedimentation plants.

it is a general object of this invention to provide improved systems of the aforementioned character.

It is a special object of this invention to provide improved control means for operating sedimentation tanks either manually or preferably semi-automatically or fully automatically.

Another object of the invention is to provide reliable means for measuring the density of media including a liquid phase and a solid phase suspended therein.

Another object of the invention is to provide means for measuring the density of media including a liquid phase and a solid phase suspended therein which means do not depend upon visual observation of such media and are not subject to errors resulting from changes in the color or light absorption of such media.

Another object of the invention is to provide sedimentation systems which lend themselves well to manual, semi automatic, or fully automatic control.

Still another object of the invention is to provide sedimentation systems including radioactive measuring and control means which ensure "a high degree of uniformity of the output of such systems, i.e. a high degree of uniformity of the density of their output.

Other objects and advantages of the invention will, in part, be obvious and in part appear hereinafter.

For a more complete understanding of the invention reference may be had to the following detailed descrip tion thereof taken in connection with the accompanying drawings wherein FIG. 1 shows partly in side elevation and partly in vertical section a density measuring system embodying this invention;

FIG. 2 is a top plan view of the structure of FIG. 1, and

1G. 3 is a diagrammatic representation of a sedimentation system involving the present invention.

Referring now to the drawings, and more particularly to FIGS. 1 and 2 thereof, numeral 1 has been applied to indicate a base plate supporting a length of pipe 3 by means of legs 2. Pipe 3 comprises a substantially straight middle portion and a pair of bent end portions. The middle portion of pipe 3 is of considerable length and the bent end portions of pipe 3 are relatively short. In the embodiment of FIGS. 1 and 2 pipe 3 is substantially U-shaped. Numeral 4 has been applied to indicate the left bent end portion of pipe 3. A radioactive substance 6 is arranged adjacent bent end portion 4 in spaced relation therefrom. Substance 6 may be any suitable isotope derived from the operation of an atomic reactor, or any suitable radioactive waste product. Substance 6 is associated with shielding means allowing the emission of radiation therefrom substantially only in a direction longitudinally of the straight middle portion of the length of pipe 3. The shielding means for the radioactive substance 6 include a spherical body of lead housing the radioactive substance and a tubular shielding means arranged "ice in abutting and coaxial relation to bent end portion 4 and substantially coextensive with the space bounded by spherical body 5 and bent end portion 4. Spherical body 5 is provided with a horizontal passageway making it possible to insert into it a capsule 7 which receives the radioactive substance 6. The left side of the horizontal passageway in spherical body 5 (see FIG. 1) is closed by a solid plug 8 precluding emission of radiation from substance 6 toward the left. The right side of the horizontal passageway in spherical body 5 (see FIG. 1) is closed by a plug it having a central or axial bore 9. Shielding of radiation emitted from substance 6 is further effected by body 11 having a central or axial bore 12 and by body 14 having a central or axial bore 15. Body 14 is directly affixed to part 4 and body 11 is supported by a frame 13. Numeral 17 has been applied .to indicate another frame or bracket pivotally supported at 16. The left side of frame 17 (as seen in FIGS. 1 and 2) supports an adjustment screw 18 for tightening the unit 5 so as to preclude emission of radiation therefrom except in a direction longitudinally of the middle portion of pipe 3. A receiver responsive to radiation emitted from the radioactive substance 6 is arranged adjacent the right bent end 19 of pipe 3 and exposed to radiation emitted from radioactive sub stance 6 and propagated in a direction longitudinally of the straight middle portion of pipe 3. The aforementioned receiver may be a Geiger counter 26 secured to part 19 by means of a bracket 21.

Because of the considerable length of the straight middle portion of pipe 3, the contents of solid matter suspended in a liquid flowing through pipe 3 will have a significant efiect upon the indications of Geiger counter 20. Hence the indications of Geiger counter 29 will be a reasonably precise measure for the amount of solid matter suspended in a flow of liquid passing through pipe 3.

Referring now to FIG. 3, numeral 23 has been applied to indicate a sedimentation tank including a bottom portion 22 substantially in the shape of an inverted cone. The pipe 24 is connected to the lower end of cone 22 for withdrawing semi-liquid matter or mud deposited therein. Valve 26 adapted to be operated by electric motor 25 controls the flow through pipe means 24. A second pipe 28 is connected to core 22 adjacent the upper end thereof. Pipe 28 by-passes valve 26 and is connected to pipe 24 at a point thereof situated downstream from valve 26. Valve 39 operated by a motor means 29 such as, for instance, an electric motor or an electromagnet, controls the flow through pipe 28. A radioactive substance is arranged adjacent cone 22 at a level slightly below the point of connection between pipe 28 and cone 22. The radio active substance is housed in a spherical shielding body 13 of lead which is of substantially the same nature as the element indicated in FIGS. 1 and 2 by numeral 5. The shielding body 31 has a horizontal bore for directing a first substantially horizontal beam M of radiation from the radioactive substance housed in it transversely across cone 22. A first receiver 32 responsive to said radiation, e.g. a Geiger counter, is arranged to intercept the beam M upon having passed through the upper region of cone 22 where the density of solid matter is relatively low as long as the inverted cone 22 is not filled with products of sedimentation or mud. Geiger counter 32 controls an amplifier 34. The output of amplifier 34, in turn, controls a meter 39 having a pair of hands 41, 42. The position of hand 41 is controlled by amplifier 34, and hand 41 indicates density of the semiliquid or mud at the upper level of cone 22, while hand 42 is adapted to indicate the density of the semi-liquid or mud inside of pipe 24. The scale of meter 39 may be calibrated, for instance, in terms of ounces of solid matter per gallon of water. If desired a. recording instrument 43 may be connected in parallel to the meter 39. Meter 39, recording instrument 43 and other parts may be energized from feeder or line 44. Instrument 43 draws graphs showing the amounts of solid matter contained in each unit of water plotted versus time. The output of Geiger counter 33 intercepting the vertical beam M emitted from body 31 is fed into amplifier 35 and the output of the latter is fed into meter 39 and controls the position of hand 42 thereof. The difierence between the positions of hands 41 and 42 is an indication of the condition the sedimentation system in.

The sedimentation system can be operated manually, semi-automatically and fully automatically. FIG. 3 in cludes all the parts required for entirely automatic operation of the system. These parts and the operation thereof will be considered below more in detail.

Numeral 27 has been applied to indicate a pump and motor unit for removing semi-liquid matter from the lower end of inverted cone 22. The pump forming an integral part of this unit is built into pipeline 24.

Hand 41 indicates the density of the semi-liquid matter or mud at the upper level of inverted cone 22. When the density indicated by hand 41 is sufiiciently high or at a predetermined value the person in charge of operating the system starts the pump and motor unit 27 and causes motor 25 to open valve means 26. Now inverted cone 22 is being emptied into and through pipeline 24. Assuming that the density value indicated by hand 42 of meter 39 exceeds the density value indicated by hand 41, then the person in charge of operating the system Will cause motor means 29 to open valve means 30. As a result, water or a semi-liquid having a relatively low content of solid matter in fine suspension will be admitted to pipe 24 by means of by-pass 28. Such a dilution of sediments removed from the lower end of inverted cone 22 is necessary in the interest of achieving satisfactory action of pump 27. If the content of solid matter in the portion of pipe 24 exposed to beam M is too small, the indication of hand 42 will become less than that of hand 41, in which case the person operating the system should cause motor means 25 to partially close valve means 26.

For fully automatic operation meter 39 is associated with automatic regulating means responsive to the difference between the positions of hands 41 and 42. Such regulating means are well known in the art and, therefore, do not need to be described here in detail. As soon as the density of the medium exposed to beam M reaches a predetermined value, Geiger counter 32 energizes a relay 36 by the intermediary of amplifier 34 and meter-regulator 39. This, in turn, causes energization of relays 37 and 38. Relay 37 starts the motor and pump unit 27 and relay 38 starts motor 25 operating, i.e. opening valve means 26. Seal-in means associated with the circuit of motor and pump unit 27 maintain that unit in operation until the circuitry of meter regulator 39 is energized by Geiger counter 33 and amplifier 34.

Assuming that the actual density value indicated by hand 42 exceeds the density value indicated by hand 41, then the meter-regulator 39 will give an impulse to a relay 40 which controls the motor means for operating valve means 30, causing opening of valve means 30. Opening of valve 30 causes dilution of the medium flowing through pipe 24 until hands 41 and 42 assume the same position or, in other words, until the actual density of the medium flowing through pipe 24 is equal to the desired density thereof.

It the density of the medium exposed to the beam M is less than the required density, meter regulator 39 will cause operation of reversing relay 38, reversing the direction of motor 25, so as to close valve means 26. At a critical minimum density of the medium or mud in pipe 24 exposed to beam M relay 38 causes complete closure of valve means 26 and also interruption of the operation of the motor pump unit 27 by acting upon start and stop relay 37. The system then remains at rest until such time when the density of matter inside beam M is sufiiciently high to initiate automatic draining of cone 22 through pipe 24.

Valve 26 opens initially and the pump and motor unit 27 begins initially to operate when the sedimentation tank is filled and when the mud in the bottom portion 22 of the sedimentation tank reaches a predetermined consistency. When the sensing system in pipe 24 responds to a substandard consistency of the muddy mixture of water and solid matter flowing through pipe 24, valve 26 is reclosed and the pump and motor unit rendered inefiective. Valve 26 must not necessarily be moved all the Way to its full closing position, such partial closing occurring when, as a result of a partial closing the consistency of the mixture flowing through valve 26 is increased to the standard consistency level. However, if a partial closing of valve 26 does not result in a sufiicient increase of the consistency of the mixture flowing through valve 26 and pipe 24 then the response of the sensing system in pipe 24 results in a complete closing of valve 26.

It may occur that the muddy matter collected in the bottom portion 22 of the sedimentation tank is too thick, i.e. its consistency too high and, that on account of this fact, the pump and motor unit 27 is not capable of properly performing its function, Under such circumstances valve 30 is caused to open and hence the consistency of the muddy matter in pipe 24 reduced. As the consistency of matter flowing through pipe 24 decreases, valve 30 is being reclosed. Under such circumstances the consistency of the mixture flowing through pipe 24 may become too small, and in response the sensing system in pipe 24 may react by wholly or partially closing valve 26. This is as it should be since the object of the present automatic control system is to preclude too much water from being pumped -by pump and motor unit 27 to a processing sta tion located at a point downstream of unit 27.

It is thus apparent that valve 26 opens only after a muddy mixture of water and solid matter of predetermined consistency has been established, and valve 26 closes subsequent to a temporary opening of valve 30, resulting in too great a dilution of the mixture in pipe 24 and valve 26 closes also in case of such a dilution not preceded by an opening of valve 30.

In some special instances the density at the top of inverted cone 22 may reach a predetermined value within regular intervals of time. In such instances starting of unit 27 and opening of valve 26 maybe effected by a clock mechanism. Stopping of unit 27 and closing of valve 26 may be effected automatically by the above described means sensitive to radiation emitted from a radioactive substance.

It will be noted from a comparison of FIGS. 1 and 2, on the one hand, and of FIG. 3, on the other hand, that the structures shown therein have some common features, and some difierent features. The common features consist in that in both instances one of a pair of elbows is arranged adjacent one end of a straight pipe line of considerable length, each having a radius of curvature relatively short in comparison to the length of the pipe line, and each'serially connected to the pipe line, and in that in both instances the emitter as well as the receiver are each arranged adjacent one of said pair of elbows on the outside thereof at points more remote from the centers of curvature of said pair of elbows than the radially outer surfaces of said pair of elbows. The structure of FIG. 3 differs from that of FIGS. 1 and 2 in that in the latter the relatively long pipe line is arranged horizontally, while in the former the relatively long pipe line is arranged vertically. The structure of FIG. 3 further difiers from the structure of FIGS. 1 and 2 in that in the former the relatively long pipe line and its two elbows form a substantially Z-shaped unit, while in the latter the relatively long pipe line and its two elbows form a substantially U-shaped unit. The arrangement of parts of FIG. 3 is preferable wherever the sensing means for determining the liquid-to-solid-matter ratio is associated with an 5 inverted cone type sedimentation tank of considerable height since the vertical arrangement of the pipe line requires but a very small square footage and since the head of the liquid in the vertical pipe line Will be as high as the level in the sedimentation tank, thus minimizing wori: required in pumping operations.

Having disclosed preferred embodiments of my invention it is desired that the same not be limited to the particular structure disclosed. It will be obvious to any person skilled in the art that many modifications and changes may be made Without departing from the broad spirit and scope of my invention. Therefore it is desired that the invention be interpreted as broadly as possible, and that it be limited only as required by the prior state of the art.

I claim as my invention:

1. In a system for controlling the flow of liquids including comminuted solid matter suspended therein the combination of means defining a sedimentation tank, a first pipe means connected to a point of said tank adjacent the bottom thereof adapted to Withdraw semi-liquid matter from said tank deposited adjacent the bottom thereof, a first valve means for controlling the flow through said first pipe means, a second pipe means connected to said tank at a higher level than said first pipe means adapted to Withdraw liquid matter from said tank having a relatively small content of sediment matter, said second pipe means by-passing said first valve means and being connected to said first pipe means at a point thereof situated downstream from said first valve means, a second valve means for controlling the flow through said second pipe means, radioactive means for establishing a first substantially horizontal beam of radiation across said tank at a level situated above said point of said tank, a first receiver responsive to said radiation arranged to intercept said first beam, radioactive means for establishing a second beam of radiation extending through a portion of said first pipe means in a direction substantially longitudinally of said portion, a second receiver responsive to said radiation arranged to intercept said second beam upon propagation thereof in a direction longitudinally of said portion of said first pipe means, means responsive to said first receiver for causing opening of said first valve, means responsive to said second receiver for causing closing of said first valve, and means responsive to the difference of the responses of said first receiver and of said second receiver for controlling said second valve.

2. in a system for controlling the flow of liquids including comminuted solid matter suspended therein the combination of a sedimentation tank, pipe means connected to a point of said tank adjacent the bottom thereof adapted to Withdraw semi-liquid matter from said tank deposited adjacent the bottom thereof, valve means controlling floW through said pipe means, motor means adapted to operate in opposite directions to open and to close said valve means, radioactive means for establishing a first substantially horizontal beam of radiation across said tank at a relatively high level thereof, a first receiver responsive to said radiation arranged to intercept said first beam, radioactive means for establishing a second beam of radiation extending through a portion of said pipe means in a direction substantially longitudinally of said portion, a second receiver responsive to said radiation arranged to intercept said second beam, means responsive to said first receiver for causing said motor means to open said valve, and means responsive to: said second receiver for causing said motor means to close said valve.

References (Iited in the file of this patent UNITED STATES PATENTS 2,454,653 Kamp Nov. 23, 1948 2,661,550 Graham Dec. 8, 1953 2,833,929 Barleau May 6, 1958 

1. IN A SYSTEM FOR CONTROLLING THE FLOW OF LIQUIDS INCLUDING COMMINUTED SOLID MATTER SUSPENDED THEREIN THE COMBINATION OF MEANS DEFINING A SEDIMENTATION TANK, A FIRST PIPE MEANS CONNECTED TO A POINT OF SAID TANK ADJACENT THE BOTTOM THEREOF ADAPTED TO WITHDRAW SEMI-LIQUID MATTER FROM SAID TANK DEPOSITED ADJACENT THE BOTTOM THEROF, A FIRST VALVE MEANS FOR CONTROLLING THE FLOW THROUGH SAID FIRST PIPE MEANS, A SECOND PIPE MEANS CONNECTED TO SAID TANK AT A HIGHER LEVEL THAN SAID FIRST PIPE MEANS ADAPTED TO WITHDRAW LIQUID MATTER FROM SAID TANK HAVING A RELATIVELY SMALL CONTENT OF SEDIMENT MATTER, SAID SECOND PIPE MEANS BY-PASSING SAID FIRST VALVE MEANS AND BEING CONNECTED TO SAID FIRST PIPE MEANS AT A POINT THEREOF SITUATED DOWNSTREAM FROM SAID FIRST VALVE MEANS, A SECOND VALVE MEANS FOR CONTROLLING THE FLOW THROUGH SAID SECOND PIPE MEANS, RADIOACTIVE MEANS FOR ESTABLISHING A FIRST SUBSTANTIALLY HORIZONTAL BEAM OF RADIATION ACROSS SAID TANK AT A LEVEL SITUATED ABOVE SAID POINT OF SAID TANK, A FIRST RECEIVER REPONSIVE TO SAID RADIATION ARRANGED TO INTERCEPT SAID FIRST BEAM, RADIOATIVE MEANS FOR ESTABLISHING A SECOND BEAM OF RADIATION EXTENDING THROUGH A PORTION OF SAID FIRST PIPE MEANS IN A DIRECTION SUBSTANTIALLY LONGI- 